This invention relates to the preservation of living tissue in the absence of oxygenation or in the event of insufficient oxygenation by the blood.
Under normal oxygenation conditions, reduction of the oxygen by the mitochondrial respiratory system supplies most of the energy emanating from the catabolism of the fatty acids and glucides in the form of adenosine triphosphate (ATP).
The reduction in the ATP and creatinine phosphate content of tissues which occurs in periods of non-oxygenation (anoxia) or insufficient irrigation (ischemia) by the blood promotes the development of irreversible cell changes during those periods and during reoxygenation of the tissues.
When the tissue is not irrigated and deprived of oxygen, the fermentation of glucose into lactate does supply some energy, but is accompanied by acidification of the cytoplasm of the cell due to the accumulation of lactate. This intracellular acidification impedes the metabolism and compromises the resumption of function of the tissue when irrigation and oxygenation resume.
The hypothesis has been put forward that, in certain animals, the metabolism under anaerobic conditions of aspartate and glutamate into succinate was linked to the non-oxidative phosphorylation of adenosine diphosphate (ADP) occurring inside the mitochondria (Hochachka, P., Owen, T.G., Amer. Zool. 13: 543-555, 1973).
On the other hand, the effect of intravenous infusion of glycerol monoacetoacetate as a non-protein energy source in burnt rats has been described and it has been shown that this compound can replace glucose as a source of energy during parenteral nutrition (Maiz, A., Moldawer, L.L., Bistrian, B.R., Biochem. J., 1985, 226/1, 43-50).